<!DOCTYPE HTML>
<html lang="zh-CN">


<head>
    <meta charset="utf-8">
    <meta name="keywords" content="Linux权能与PAM机制, Xsyin">
    <meta name="description" content="Go go">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, user-scalable=no">
    <meta name="renderer" content="webkit|ie-stand|ie-comp">
    <meta name="mobile-web-app-capable" content="yes">
    <meta name="format-detection" content="telephone=no">
    <meta name="apple-mobile-web-app-capable" content="yes">
    <meta name="apple-mobile-web-app-status-bar-style" content="black-translucent">
    <!-- Global site tag (gtag.js) - Google Analytics -->


    <title>Linux权能与PAM机制 | Xsyin</title>
    <link rel="icon" type="image/png" href="/favicon.png">

    <link rel="stylesheet" type="text/css" href="/libs/awesome/css/all.css">
    <link rel="stylesheet" type="text/css" href="/libs/materialize/materialize.min.css">
    <link rel="stylesheet" type="text/css" href="/libs/aos/aos.css">
    <link rel="stylesheet" type="text/css" href="/libs/animate/animate.min.css">
    <link rel="stylesheet" type="text/css" href="/libs/lightGallery/css/lightgallery.min.css">
    <link rel="stylesheet" type="text/css" href="/css/matery.css">
    <link rel="stylesheet" type="text/css" href="/css/my.css">

    <script src="/libs/jquery/jquery.min.js"></script>

<meta name="generator" content="Hexo 6.3.0"></head>




<body>
    <header class="navbar-fixed">
    <nav id="headNav" class="bg-color nav-transparent">
        <div id="navContainer" class="nav-wrapper container">
            <div class="brand-logo">
                <a href="/" class="waves-effect waves-light">
                    
                    <img src="/medias/logo.png" class="logo-img" alt="LOGO">
                    
                    <span class="logo-span">Xsyin</span>
                </a>
            </div>
            

<a href="#" data-target="mobile-nav" class="sidenav-trigger button-collapse"><i class="fas fa-bars"></i></a>
<ul class="right nav-menu">
  
  <li class="hide-on-med-and-down nav-item">
    
    <a href="/" class="waves-effect waves-light">
      
      <i class="fas fa-home" style="zoom: 0.6;"></i>
      
      <span>首页</span>
    </a>
    
  </li>
  
  <li class="hide-on-med-and-down nav-item">
    
    <a href="/tags" class="waves-effect waves-light">
      
      <i class="fas fa-tags" style="zoom: 0.6;"></i>
      
      <span>标签</span>
    </a>
    
  </li>
  
  <li class="hide-on-med-and-down nav-item">
    
    <a href="/categories" class="waves-effect waves-light">
      
      <i class="fas fa-bookmark" style="zoom: 0.6;"></i>
      
      <span>分类</span>
    </a>
    
  </li>
  
  <li class="hide-on-med-and-down nav-item">
    
    <a href="/archives" class="waves-effect waves-light">
      
      <i class="fas fa-archive" style="zoom: 0.6;"></i>
      
      <span>归档</span>
    </a>
    
  </li>
  
  <li class="hide-on-med-and-down nav-item">
    
    <a href="/about" class="waves-effect waves-light">
      
      <i class="fas fa-user-circle" style="zoom: 0.6;"></i>
      
      <span>关于</span>
    </a>
    
  </li>
  
  <li class="hide-on-med-and-down nav-item">
    
    <a href="/contact" class="waves-effect waves-light">
      
      <i class="fas fa-comments" style="zoom: 0.6;"></i>
      
      <span>留言板</span>
    </a>
    
  </li>
  
  <li class="hide-on-med-and-down nav-item">
    
    <a href="/friends" class="waves-effect waves-light">
      
      <i class="fas fa-address-book" style="zoom: 0.6;"></i>
      
      <span>友情链接</span>
    </a>
    
  </li>
  
  <li>
    <a href="#searchModal" class="modal-trigger waves-effect waves-light">
      <i id="searchIcon" class="fas fa-search" title="搜索" style="zoom: 0.85;"></i>
    </a>
  </li>
</ul>


<div id="mobile-nav" class="side-nav sidenav">

    <div class="mobile-head bg-color">
        
        <img src="/medias/logo.png" class="logo-img circle responsive-img">
        
        <div class="logo-name">Xsyin</div>
        <div class="logo-desc">
            
            Go go
            
        </div>
    </div>

    

    <ul class="menu-list mobile-menu-list">
        
        <li class="m-nav-item">
	  
		<a href="/" class="waves-effect waves-light">
			
			    <i class="fa-fw fas fa-home"></i>
			
			首页
		</a>
          
        </li>
        
        <li class="m-nav-item">
	  
		<a href="/tags" class="waves-effect waves-light">
			
			    <i class="fa-fw fas fa-tags"></i>
			
			标签
		</a>
          
        </li>
        
        <li class="m-nav-item">
	  
		<a href="/categories" class="waves-effect waves-light">
			
			    <i class="fa-fw fas fa-bookmark"></i>
			
			分类
		</a>
          
        </li>
        
        <li class="m-nav-item">
	  
		<a href="/archives" class="waves-effect waves-light">
			
			    <i class="fa-fw fas fa-archive"></i>
			
			归档
		</a>
          
        </li>
        
        <li class="m-nav-item">
	  
		<a href="/about" class="waves-effect waves-light">
			
			    <i class="fa-fw fas fa-user-circle"></i>
			
			关于
		</a>
          
        </li>
        
        <li class="m-nav-item">
	  
		<a href="/contact" class="waves-effect waves-light">
			
			    <i class="fa-fw fas fa-comments"></i>
			
			留言板
		</a>
          
        </li>
        
        <li class="m-nav-item">
	  
		<a href="/friends" class="waves-effect waves-light">
			
			    <i class="fa-fw fas fa-address-book"></i>
			
			友情链接
		</a>
          
        </li>
        
        
        <li><div class="divider"></div></li>
        <li>
            <a href="https://github.com/blinkfox/hexo-theme-matery" class="waves-effect waves-light" target="_blank">
                <i class="fab fa-github-square fa-fw"></i>Fork Me
            </a>
        </li>
        
    </ul>
</div>


        </div>

        
            <style>
    .nav-transparent .github-corner {
        display: none !important;
    }

    .github-corner {
        position: absolute;
        z-index: 10;
        top: 0;
        right: 0;
        border: 0;
        transform: scale(1.1);
    }

    .github-corner svg {
        color: #0f9d58;
        fill: #fff;
        height: 64px;
        width: 64px;
    }

    .github-corner:hover .octo-arm {
        animation: a 0.56s ease-in-out;
    }

    .github-corner .octo-arm {
        animation: none;
    }

    @keyframes a {
        0%,
        to {
            transform: rotate(0);
        }
        20%,
        60% {
            transform: rotate(-25deg);
        }
        40%,
        80% {
            transform: rotate(10deg);
        }
    }
</style>

<a href="https://github.com/blinkfox/hexo-theme-matery" class="github-corner tooltipped hide-on-med-and-down" target="_blank"
   data-tooltip="Fork Me" data-position="left" data-delay="50">
    <svg viewBox="0 0 250 250" aria-hidden="true">
        <path d="M0,0 L115,115 L130,115 L142,142 L250,250 L250,0 Z"></path>
        <path d="M128.3,109.0 C113.8,99.7 119.0,89.6 119.0,89.6 C122.0,82.7 120.5,78.6 120.5,78.6 C119.2,72.0 123.4,76.3 123.4,76.3 C127.3,80.9 125.5,87.3 125.5,87.3 C122.9,97.6 130.6,101.9 134.4,103.2"
              fill="currentColor" style="transform-origin: 130px 106px;" class="octo-arm"></path>
        <path d="M115.0,115.0 C114.9,115.1 118.7,116.5 119.8,115.4 L133.7,101.6 C136.9,99.2 139.9,98.4 142.2,98.6 C133.8,88.0 127.5,74.4 143.8,58.0 C148.5,53.4 154.0,51.2 159.7,51.0 C160.3,49.4 163.2,43.6 171.4,40.1 C171.4,40.1 176.1,42.5 178.8,56.2 C183.1,58.6 187.2,61.8 190.9,65.4 C194.5,69.0 197.7,73.2 200.1,77.6 C213.8,80.2 216.3,84.9 216.3,84.9 C212.7,93.1 206.9,96.0 205.4,96.6 C205.1,102.4 203.0,107.8 198.3,112.5 C181.9,128.9 168.3,122.5 157.7,114.1 C157.9,116.9 156.7,120.9 152.7,124.9 L141.0,136.5 C139.8,137.7 141.6,141.9 141.8,141.8 Z"
              fill="currentColor" class="octo-body"></path>
    </svg>
</a>
        
    </nav>

</header>

    



<div class="bg-cover pd-header post-cover" style="background-image: url('/medias/featureimages/8.jpg')">
    <div class="container" style="right: 0px;left: 0px;">
        <div class="row">
            <div class="col s12 m12 l12">
                <div class="brand">
                    <h1 class="description center-align post-title">Linux权能与PAM机制</h1>
                </div>
            </div>
        </div>
    </div>
</div>




<main class="post-container content">

    
    <link rel="stylesheet" href="/libs/tocbot/tocbot.css">
<style>
    #articleContent h1::before,
    #articleContent h2::before,
    #articleContent h3::before,
    #articleContent h4::before,
    #articleContent h5::before,
    #articleContent h6::before {
        display: block;
        content: " ";
        height: 100px;
        margin-top: -100px;
        visibility: hidden;
    }

    #articleContent :focus {
        outline: none;
    }

    .toc-fixed {
        position: fixed;
        top: 64px;
    }

    .toc-widget {
        width: 345px;
        padding-left: 20px;
    }

    .toc-widget .toc-title {
        padding: 35px 0 15px 17px;
        font-size: 1.5rem;
        font-weight: bold;
        line-height: 1.5rem;
    }

    .toc-widget ol {
        padding: 0;
        list-style: none;
    }

    #toc-content {
        padding-bottom: 30px;
        overflow: auto;
    }

    #toc-content ol {
        padding-left: 10px;
    }

    #toc-content ol li {
        padding-left: 10px;
    }

    #toc-content .toc-link:hover {
        color: #42b983;
        font-weight: 700;
        text-decoration: underline;
    }

    #toc-content .toc-link::before {
        background-color: transparent;
        max-height: 25px;

        position: absolute;
        right: 23.5vw;
        display: block;
    }

    #toc-content .is-active-link {
        color: #42b983;
    }

    #floating-toc-btn {
        position: fixed;
        right: 15px;
        bottom: 76px;
        padding-top: 15px;
        margin-bottom: 0;
        z-index: 998;
    }

    #floating-toc-btn .btn-floating {
        width: 48px;
        height: 48px;
    }

    #floating-toc-btn .btn-floating i {
        line-height: 48px;
        font-size: 1.4rem;
    }
</style>
<div class="row">
    <div id="main-content" class="col s12 m12 l9">
        <!-- 文章内容详情 -->
<div id="artDetail">
    <div class="card">
        <div class="card-content article-info">
            <div class="row tag-cate">
                <div class="col s7">
                    
                    <div class="article-tag">
                        
                            <a href="/tags/Linux-capability/">
                                <span class="chip bg-color">Linux capability</span>
                            </a>
                        
                    </div>
                    
                </div>
                <div class="col s5 right-align">
                    
                    <div class="post-cate">
                        <i class="fas fa-bookmark fa-fw icon-category"></i>
                        
                            <a href="/categories/Linux/" class="post-category">
                                Linux
                            </a>
                        
                    </div>
                    
                </div>
            </div>

            <div class="post-info">
                
                <div class="post-date info-break-policy">
                    <i class="far fa-calendar-minus fa-fw"></i>发布日期:&nbsp;&nbsp;
                    2018-05-01
                </div>
                

                

                

                

                
            </div>
        </div>
        <hr class="clearfix">

        

        

        <div class="card-content article-card-content">
            <div id="articleContent">
                <blockquote>
<p>实验环境：<code>uname -a</code></p>
<p>​      <code>Linux ubuntu 4.4.0-121-generic #145-Ubuntu SMP Fri Apr 13 13:47:23 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux</code></p>
</blockquote>
<hr>
<h3 id="权能对应的系统调用"><a href="#权能对应的系统调用" class="headerlink" title="权能对应的系统调用"></a>权能对应的系统调用</h3><p>使用 <code>sudo find / -name capability.h </code> 查找到路径 <code>/usr/src/linux-headers-4.4.0-121/include/uapi/linux/capbility.h</code>  ，整理可得下表：</p>
<span id="more"></span>

<table>
<thead>
<tr>
<th>权能</th>
<th>编号(相关系统调用）</th>
<th>解释</th>
</tr>
</thead>
<tbody><tr>
<td>CAP_CHOWN</td>
<td>0(chown)</td>
<td>对文件的UIDs和GIDs做任意修改</td>
</tr>
<tr>
<td>CAP_DAC_OVERRIDE</td>
<td>1</td>
<td>忽略对文件的DAC访问限制</td>
</tr>
<tr>
<td>CAP_DAC_READ_SEARCH</td>
<td>2</td>
<td>忽略DAC中对文件和目录的读、搜索权限</td>
</tr>
<tr>
<td>CAP_FOWNER</td>
<td>3</td>
<td>忽略进程UID与文件UID的匹配检查</td>
</tr>
<tr>
<td>CAP_FSETID</td>
<td>4</td>
<td>文件修改时不清除setuid和setgid位，不匹配时设置setgid位</td>
</tr>
<tr>
<td>CAP_KILL</td>
<td>5(kill)</td>
<td>绕过发送信号时的权限检查</td>
</tr>
<tr>
<td>CAP_SETGID</td>
<td>6(setgid)</td>
<td>设置或管理进程GID</td>
</tr>
<tr>
<td>CAP_SETUID</td>
<td>7(setuid)</td>
<td>管理或设置进程UID</td>
</tr>
<tr>
<td>CAP_SETPCAP</td>
<td>8(capset)</td>
<td>允许授予或删除其他进程的任何权能</td>
</tr>
<tr>
<td>CAP_LINUX_IMMUTABLE</td>
<td>9(chattr)</td>
<td>允许设置文件的不可修改位(IMMUTABLE)和只添加(APPND-ONLY)属性</td>
</tr>
<tr>
<td>CAP_NET_BIND_SERVICE</td>
<td>10</td>
<td>允许绑定到小于1024的端口</td>
</tr>
<tr>
<td>CAP_NET_BROADCAST</td>
<td>11</td>
<td>允许socket发送监听组播</td>
</tr>
<tr>
<td>CAP_NET_ADMIN</td>
<td>12</td>
<td>允许执行网络管理任务</td>
</tr>
<tr>
<td>CAP_NET_RAW</td>
<td>13(socket)</td>
<td>允许使用原始套接字</td>
</tr>
<tr>
<td>CAP_IPC_LOCK</td>
<td>14(mlock)</td>
<td>允许锁定共享内存片段</td>
</tr>
<tr>
<td>CAP_IPC_OWNER</td>
<td>15</td>
<td>忽略IPC所有权检查</td>
</tr>
<tr>
<td>CAP_SYS_MOUDLE</td>
<td>16(init_module)</td>
<td>插入和删除内核模块</td>
</tr>
<tr>
<td>CAP_SYS_RAWIO</td>
<td>17</td>
<td>允许对ioperm&#x2F;iopl的访问</td>
</tr>
<tr>
<td>CAP_SYS_CHROOT</td>
<td>18(chroot)</td>
<td>允许使用chroot()系统调用</td>
</tr>
<tr>
<td>CAP_SYS_PTRACE</td>
<td>19(ptrace)</td>
<td>允许跟踪任何进程</td>
</tr>
<tr>
<td>CAP_SYS_PACCT</td>
<td>20(acct)</td>
<td>允许配置进程记账</td>
</tr>
<tr>
<td>CAP_SYS_ADMIN</td>
<td>21</td>
<td>允许执行系统管理任务</td>
</tr>
<tr>
<td>CAP_SYS_BOOT</td>
<td>22(reboot)</td>
<td>允许重新启动系统</td>
</tr>
<tr>
<td>CAP_SYS_NICE</td>
<td>23(nice)</td>
<td>允许提升优先级，设置其他进程优先级</td>
</tr>
<tr>
<td>CAP_SYS_RESOURCE</td>
<td>24(setrlimit)</td>
<td>设置资源限制</td>
</tr>
<tr>
<td>CAP_SYS_TIME</td>
<td>25(stime)</td>
<td>允许改变系统时钟</td>
</tr>
<tr>
<td>CAP_SYS_TTY_CONFIG</td>
<td>26(vhangup)</td>
<td>允许配置TTY设备</td>
</tr>
<tr>
<td>CAP_MKNOD</td>
<td>27(mknod)</td>
<td>允许使用mknod()系统调用，创建特殊文件</td>
</tr>
<tr>
<td>CAP_LEASE</td>
<td>28(fcntl)</td>
<td>为任意文件建立租约</td>
</tr>
<tr>
<td>CAP_AUDIT_WRITE</td>
<td>29</td>
<td>允许向内核审计日志写记录</td>
</tr>
<tr>
<td>CAP_AUDIT_CONTROL</td>
<td>30</td>
<td>启用或禁用内核审计，修改审计过滤器规则</td>
</tr>
<tr>
<td>CAP_SETFCAP</td>
<td>31</td>
<td>设置文件权能</td>
</tr>
<tr>
<td>CAP_MAC_OVERRIDE</td>
<td>32</td>
<td>允许MAC配置或状态改变，为smack LSM实现</td>
</tr>
<tr>
<td>CAP_MAC_ADMIN</td>
<td>33</td>
<td>覆盖强制访问控制</td>
</tr>
<tr>
<td>CAP_SYSLOG</td>
<td>34(syslog)</td>
<td>执行特权syslog(2)操作</td>
</tr>
<tr>
<td>CAP_WAKE_ALARM</td>
<td>35</td>
<td>触发将唤醒系统的东西</td>
</tr>
<tr>
<td>CAP_BLOCK_SUSPEND</td>
<td>36(epoll)</td>
<td>可以阻塞系统挂起的特性</td>
</tr>
<tr>
<td>CAP_AUDIT_READ</td>
<td>37</td>
<td>允许通过一个多播socket读取审计日志</td>
</tr>
</tbody></table>
<p>详情见<a target="_blank" rel="noopener" href="http://man7.org/linux/man-pages/man7/capabilities.7.html">man capabilities</a> 。</p>
<hr>
<h3 id="基于PAM用户权限设置系统"><a href="#基于PAM用户权限设置系统" class="headerlink" title="基于PAM用户权限设置系统"></a>基于PAM用户权限设置系统</h3><p>PAM 的全称为“可插拔认证模块（Pluggable Authentication Modules）”。设计的初衷是将不同的底层认证机制集中到一个高层次的API中，从而省去开发人员自己去设计和实现各种繁杂的认证机制的麻烦。</p>
<p>PAM认证一般遵循这样的顺序：Service(服务)→PAM(配置文件)→pam_*.so，PAM配置文件在<code>/etc/pam.d/</code> 目录下，原理图如下：</p>
<p><img src="/pam.png" alt="pam"></p>
<p>PAM中配置字段：</p>
<figure class="highlight text"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">moudle_type  control_flag  moudle_path moudle_option/moudle_args</span><br></pre></td></tr></table></figure>

<ol>
<li><code>module_type</code> 为 相应服务指定模块类型</li>
</ol>
<table>
<thead>
<tr>
<th>模块类型</th>
<th>说明</th>
</tr>
</thead>
<tbody><tr>
<td>auth(验证模块)</td>
<td>用于验证用户或设置&#x2F;销毁凭证</td>
</tr>
<tr>
<td>account(帐户管理模块)</td>
<td>将执行与访问、帐户及凭证有效期、密码限制&#x2F;规则等有关的操作</td>
</tr>
<tr>
<td>session(会话管理模块)</td>
<td>定义用户登录前的,及用户退出后所要进行的操作.如:登录连接信息,用户数据的打开与关闭,挂载文件系统等</td>
</tr>
<tr>
<td>passwd(密码管理模块)</td>
<td>将执行与密码更改&#x2F;更新有关的操作</td>
</tr>
</tbody></table>
<ol start="2">
<li>control_flag 将指定模块的堆栈行为，配置文件中列出模块被调用的顺序</li>
</ol>
<table>
<thead>
<tr>
<th>控制标记</th>
<th>说明</th>
</tr>
</thead>
<tbody><tr>
<td>required</td>
<td>堆栈中的所有 required 模块必须看作一个成功的结果。如果一个或多个 required 模块失败，则实现堆栈中的所有 required 模块，但是将返回第一个错误</td>
</tr>
<tr>
<td>requisite</td>
<td>如果本模块没有被满足，那本次认证一定失败，而且整个栈立即中止并返回错误信号</td>
</tr>
<tr>
<td>sufficient</td>
<td>如果标记为 sufficient 的模块成功并且先前没有 required 或 sufficient 模块失败，则忽略堆栈中的所有其余模块并返回成功</td>
</tr>
<tr>
<td>optional</td>
<td>如果堆栈中没有一个模块是 required 并且没有任何一个 sufficient 模块成功，则服务&#x2F;应用程序至少要有一个 optional 模块成功</td>
</tr>
<tr>
<td>include</td>
<td>包含其他规则（服务），文件嵌套，可以互相调用，如：login，auth，system-auth等</td>
</tr>
<tr>
<td>[value1&#x3D;action1  value2&#x3D;action2 ….]</td>
<td>六种动作：ok ，done，bad，die，ignore，reset。</td>
</tr>
</tbody></table>
<p>​        Example：auth [user_unknown&#x3D;ignore success&#x3D;ok ignore&#x3D;ignore default&#x3D;bad] pam_securetty.so</p>
<ol start="3">
<li><code>module_path</code> 将指定实现模块的库对象的路径名称。默认情况下，它将被设为 <code>/lib/security</code>。        <img src="/libpam.png" alt="libpam"></li>
<li>module_options&#x2F;module_args（可选字段）将指定可以传递给服务模块的选项或实参。</li>
</ol>
<hr>
<p>实验：配置用户<code>userping</code> ，设置<code>cap_net_raw</code> 权能。</p>
<ul>
<li>添加用户<code>userping</code>  :  <code>sudo adduser userping</code> </li>
<li>查看并清除<code>/bin/ping</code> 的权能：</li>
</ul>
<p><img src="/%E9%80%89%E5%8C%BA_057.png" alt="选区_057"></p>
<ul>
<li>切换到用户<code>userping</code> 再<code>ping</code> 无法<code>ping</code>   : <code>su userping</code> </li>
<li><code>userping</code> 登录时给<code>/bin/ping</code> 添加权能：</li>
</ul>
<figure class="highlight shell"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br></pre></td><td class="code"><pre><span class="line"><span class="meta prompt_">#</span><span class="language-bash"><span class="comment">####################################################</span></span></span><br><span class="line"><span class="meta prompt_"># </span><span class="language-bash">File Name: ping_cap.sh</span></span><br><span class="line"><span class="meta prompt_"># </span><span class="language-bash">Author: xsyin</span></span><br><span class="line"><span class="meta prompt_"># </span><span class="language-bash">mail: shouyinXu@163.com</span></span><br><span class="line"><span class="meta prompt_"># </span><span class="language-bash">Created Time: 2018年04月30日 星期一 16时05分57秒</span></span><br><span class="line"><span class="meta prompt_">#</span><span class="language-bash"><span class="comment">###################################################</span></span></span><br><span class="line"><span class="meta prompt_"></span></span><br><span class="line"><span class="meta prompt_">#</span><span class="language-bash">!/bin/sh</span></span><br><span class="line">[ &quot;$PAM_TYPE&quot; == &quot;open_session&quot; ] || exit 0</span><br><span class="line"></span><br><span class="line">if [ &quot;$PAM_USER&quot; == &quot;userping&quot; ]; then</span><br><span class="line">	setcap cap_net_raw=eip /bin/ping</span><br><span class="line">	echo &quot;SUCCESS&quot;</span><br><span class="line">else</span><br><span class="line">	echo &quot;FAILURE&quot;</span><br><span class="line">fi</span><br><span class="line"></span><br></pre></td></tr></table></figure>

<ul>
<li>将<code>ping_cap.sh</code> 移动到 <code>/usr/local/bin</code> 路径下，并设置为可执行：</li>
</ul>
<figure class="highlight text"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">sudo chmod u+x /usr/loca/bin/ping_cap.sh</span><br></pre></td></tr></table></figure>

<ul>
<li>所有登录都使用<code>common-session</code> 模块：</li>
</ul>
<p><img src="/%E9%80%89%E5%8C%BA_058.png" alt="选区_058"></p>
<p>因此在<code>common-session</code> 模块中添加规则: </p>
<figure class="highlight plaintext"><table><tr><td class="gutter"><pre><span class="line">1</span><br></pre></td><td class="code"><pre><span class="line">session  optional  pam_exec.so debug log=/tmp/pam_exec.log seteuid /usr/local/bin/ping_cap.sh</span><br></pre></td></tr></table></figure>

<p>必须模块，开启了<code>debug</code>模式，用户<code>userping</code> 每次登录会执行<code>ping_cap.sh</code></p>
<ul>
<li>切换到<code>userping</code> 用户：</li>
</ul>
<p><img src="/%E9%80%89%E5%8C%BA_059.png" alt="选区_059"></p>
<p>出错多次，最终调试成功：</p>
<p><img src="/%E9%80%89%E5%8C%BA_061.png" alt="选区_060"></p>
<h3 id="总结"><a href="#总结" class="headerlink" title="总结"></a>总结</h3><p>优点：<code>userping</code> 用户无法执行特权命令，通过<code>pam</code> 可赋予一些特权操作。</p>
<p>缺点：本实验中修改了<code>ping</code> 的文件权能，影响了其他用户。退出<code>userping</code> 后，<code>ping</code> 命令变成有效了。</p>
<p>过渡C版本：</p>
<figure class="highlight c"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br><span class="line">50</span><br><span class="line">51</span><br><span class="line">52</span><br><span class="line">53</span><br><span class="line">54</span><br><span class="line">55</span><br><span class="line">56</span><br></pre></td><td class="code"><pre><span class="line"><span class="comment">/*************************************************************************</span></span><br><span class="line"><span class="comment">    &gt; File Name: ping_cap.c</span></span><br><span class="line"><span class="comment">    &gt; Author: xsyin</span></span><br><span class="line"><span class="comment">    &gt; Mail: shouyinXu@163.com </span></span><br><span class="line"><span class="comment">    &gt; Created Time: 2018年04月30日 星期一 14时56分35秒</span></span><br><span class="line"><span class="comment">    &gt; Make: gcc ping_cap.c -lcap -o ping_cap</span></span><br><span class="line"><span class="comment"> ************************************************************************/</span></span><br><span class="line"></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">&lt;stdio.h&gt;</span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">&lt;stdlib.h&gt;</span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">&lt;string.h&gt;</span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">&lt;sys/types.h&gt;</span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">&lt;unistd.h&gt;</span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">&lt;sys/capability.h&gt;</span></span></span><br><span class="line"><span class="meta">#<span class="keyword">include</span> <span class="string">&lt;sys/prctl.h&gt;</span></span></span><br><span class="line"></span><br><span class="line"><span class="meta">#<span class="keyword">undef</span> _POSIX_SOURCE</span></span><br><span class="line"></span><br><span class="line"><span class="keyword">extern</span> <span class="type">int</span> errno;</span><br><span class="line"></span><br><span class="line"><span class="type">const</span> <span class="type">char</span> *path_p = <span class="string">&quot;/bin/ping&quot;</span>;</span><br><span class="line"></span><br><span class="line"><span class="type">void</span> <span class="title function_">listCaps</span><span class="params">()</span>&#123;</span><br><span class="line">    <span class="type">cap_t</span> caps = cap_get_file(path_p);</span><br><span class="line">    <span class="type">ssize_t</span> y = <span class="number">0</span>;</span><br><span class="line">    <span class="built_in">printf</span>(<span class="string">&quot;The file %s was give capabilities %s\n&quot;</span>,path_p, cap_to_text(caps, &amp;y));</span><br><span class="line">    fflush(<span class="number">0</span>);</span><br><span class="line">    cap_free(caps);</span><br><span class="line">&#125;</span><br><span class="line"></span><br><span class="line"><span class="type">int</span> <span class="title function_">main</span><span class="params">(<span class="type">int</span> argc, <span class="type">char</span> <span class="type">const</span> *argv[])</span></span><br><span class="line">&#123;</span><br><span class="line"></span><br><span class="line"></span><br><span class="line">	<span class="type">uid_t</span> uid = getuid();</span><br><span class="line"></span><br><span class="line">	<span class="keyword">if</span>(uid != <span class="number">1000</span>) </span><br><span class="line">		<span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line"></span><br><span class="line">	<span class="built_in">printf</span>(<span class="string">&quot;uid:%d\n&quot;</span>, uid);</span><br><span class="line">	</span><br><span class="line">	<span class="type">cap_value_t</span> cap_values[] = &#123;CAP_NET_RAW&#125;;</span><br><span class="line">	<span class="type">cap_t</span> caps = cap_init();</span><br><span class="line">	cap_set_flag(caps,CAP_PERMITTED,<span class="number">1</span>,cap_values,CAP_SET);</span><br><span class="line">	cap_set_flag(caps,CAP_EFFECTIVE,<span class="number">1</span>,cap_values,CAP_SET);</span><br><span class="line">	cap_set_flag(caps,CAP_INHERITABLE,<span class="number">1</span>,cap_values,CAP_SET);</span><br><span class="line">	<span class="keyword">if</span>(cap_set_file(path_p,caps))</span><br><span class="line">		perror(<span class="string">&quot;cap_set_file() ERROR: &quot;</span>);</span><br><span class="line">	<span class="keyword">else</span></span><br><span class="line">		<span class="built_in">printf</span>(<span class="string">&quot;success\n&quot;</span>);</span><br><span class="line">	cap_free(caps);</span><br><span class="line">	listCaps();</span><br><span class="line"></span><br><span class="line">	<span class="keyword">return</span> <span class="number">0</span>;</span><br><span class="line">&#125;</span><br><span class="line"></span><br></pre></td></tr></table></figure>

<p>缺陷：未搞清楚如何获取PAM正在授权的用户，无法判断切换至<code>userping</code> 用户时设置权能。</p>

                
            </div>
            <hr/>

            

    <div class="reprint" id="reprint-statement">
        
            <div class="reprint__author">
                <span class="reprint-meta" style="font-weight: bold;">
                    <i class="fas fa-user">
                        文章作者:
                    </i>
                </span>
                <span class="reprint-info">
                    <a href="/about" rel="external nofollow noreferrer">Xu Shouyin</a>
                </span>
            </div>
            <div class="reprint__type">
                <span class="reprint-meta" style="font-weight: bold;">
                    <i class="fas fa-link">
                        文章链接:
                    </i>
                </span>
                <span class="reprint-info">
                    <a href="https://Xsyin.github.io/2018/05/01/Linux%E6%9D%83%E8%83%BD%E4%B8%8EPAM%E6%9C%BA%E5%88%B6/">https://Xsyin.github.io/2018/05/01/Linux%E6%9D%83%E8%83%BD%E4%B8%8EPAM%E6%9C%BA%E5%88%B6/</a>
                </span>
            </div>
            <div class="reprint__notice">
                <span class="reprint-meta" style="font-weight: bold;">
                    <i class="fas fa-copyright">
                        版权声明:
                    </i>
                </span>
                <span class="reprint-info">
                    本博客所有文章除特別声明外，均采用
                    <a href="https://creativecommons.org/licenses/by/4.0/deed.zh" rel="external nofollow noreferrer" target="_blank">CC BY 4.0</a>
                    许可协议。转载请注明来源
                    <a href="/about" target="_blank">Xu Shouyin</a>
                    !
                </span>
            </div>
        
    </div>

    <script async defer>
      document.addEventListener("copy", function (e) {
        let toastHTML = '<span>复制成功，请遵循本文的转载规则</span><button class="btn-flat toast-action" onclick="navToReprintStatement()" style="font-size: smaller">查看</a>';
        M.toast({html: toastHTML})
      });

      function navToReprintStatement() {
        $("html, body").animate({scrollTop: $("#reprint-statement").offset().top - 80}, 800);
      }
    </script>



            <div class="tag_share" style="display: block;">
                <div class="post-meta__tag-list" style="display: inline-block;">
                    
                        <div class="article-tag">
                            
                                <a href="/tags/Linux-capability/">
                                    <span class="chip bg-color">Linux capability</span>
                                </a>
                            
                        </div>
                    
                </div>
                <div class="post_share" style="zoom: 80%; width: fit-content; display: inline-block; float: right; margin: -0.15rem 0;">
                    <link rel="stylesheet" type="text/css" href="/libs/share/css/share.min.css">
<div id="article-share">

    
    <div class="social-share" data-sites="twitter,facebook,google,qq,qzone,wechat,weibo,douban,linkedin" data-wechat-qrcode-helper="<p>微信扫一扫即可分享！</p>"></div>
    <script src="/libs/share/js/social-share.min.js"></script>
    

    

</div>

                </div>
            </div>
            
                <style>
    #reward {
        margin: 40px 0;
        text-align: center;
    }

    #reward .reward-link {
        font-size: 1.4rem;
        line-height: 38px;
    }

    #reward .btn-floating:hover {
        box-shadow: 0 6px 12px rgba(0, 0, 0, 0.2), 0 5px 15px rgba(0, 0, 0, 0.2);
    }

    #rewardModal {
        width: 320px;
        height: 350px;
    }

    #rewardModal .reward-title {
        margin: 15px auto;
        padding-bottom: 5px;
    }

    #rewardModal .modal-content {
        padding: 10px;
    }

    #rewardModal .close {
        position: absolute;
        right: 15px;
        top: 15px;
        color: rgba(0, 0, 0, 0.5);
        font-size: 1.3rem;
        line-height: 20px;
        cursor: pointer;
    }

    #rewardModal .close:hover {
        color: #ef5350;
        transform: scale(1.3);
        -moz-transform:scale(1.3);
        -webkit-transform:scale(1.3);
        -o-transform:scale(1.3);
    }

    #rewardModal .reward-tabs {
        margin: 0 auto;
        width: 210px;
    }

    .reward-tabs .tabs {
        height: 38px;
        margin: 10px auto;
        padding-left: 0;
    }

    .reward-content ul {
        padding-left: 0 !important;
    }

    .reward-tabs .tabs .tab {
        height: 38px;
        line-height: 38px;
    }

    .reward-tabs .tab a {
        color: #fff;
        background-color: #ccc;
    }

    .reward-tabs .tab a:hover {
        background-color: #ccc;
        color: #fff;
    }

    .reward-tabs .wechat-tab .active {
        color: #fff !important;
        background-color: #22AB38 !important;
    }

    .reward-tabs .alipay-tab .active {
        color: #fff !important;
        background-color: #019FE8 !important;
    }

    .reward-tabs .reward-img {
        width: 210px;
        height: 210px;
    }
</style>

<div id="reward">
    <a href="#rewardModal" class="reward-link modal-trigger btn-floating btn-medium waves-effect waves-light red">赏</a>

    <!-- Modal Structure -->
    <div id="rewardModal" class="modal">
        <div class="modal-content">
            <a class="close modal-close"><i class="fas fa-times"></i></a>
            <h4 class="reward-title">你的赏识是我前进的动力</h4>
            <div class="reward-content">
                <div class="reward-tabs">
                    <ul class="tabs row">
                        <li class="tab col s6 alipay-tab waves-effect waves-light"><a href="#alipay">支付宝</a></li>
                        <li class="tab col s6 wechat-tab waves-effect waves-light"><a href="#wechat">微 信</a></li>
                    </ul>
                    <div id="alipay">
                        <img src="/medias/reward/alipay.jpg" class="reward-img" alt="支付宝打赏二维码">
                    </div>
                    <div id="wechat">
                        <img src="/medias/reward/wechat.png" class="reward-img" alt="微信打赏二维码">
                    </div>
                </div>
            </div>
        </div>
    </div>
</div>

<script>
    $(function () {
        $('.tabs').tabs();
    });
</script>

            
        </div>
    </div>

    

    

    

    

    

    

    

    

<article id="prenext-posts" class="prev-next articles">
    <div class="row article-row">
        
        <div class="article col s12 m6" data-aos="fade-up">
            <div class="article-badge left-badge text-color">
                <i class="fas fa-chevron-left"></i>&nbsp;上一篇</div>
            <div class="card">
                <a href="/2018/05/01/Linux-%E6%9D%83%E8%83%BD%E6%9C%BA%E5%88%B6/">
                    <div class="card-image">
                        
                        
                        <img src="/medias/featureimages/18.jpg" class="responsive-img" alt="Linux 权能机制">
                        
                        <span class="card-title">Linux 权能机制</span>
                    </div>
                </a>
                <div class="card-content article-content">
                    <div class="summary block-with-text">
                        
                            
passwd​ ，  sudo​ ， ping​  等命令会修改关键文件，确保非root​ 用户无法修改，因此需要转换为root​ 用户，而setuid​ 位可以让用户暂时获得文件拥有者root​ 的身份。
以ping 命令为例，删除s 
                        
                    </div>
                    <div class="publish-info">
                        <span class="publish-date">
                            <i class="far fa-clock fa-fw icon-date"></i>2018-05-01
                        </span>
                        <span class="publish-author">
                            
                            <i class="fas fa-bookmark fa-fw icon-category"></i>
                            
                            <a href="/categories/Linux/" class="post-category">
                                    Linux
                                </a>
                            
                            
                        </span>
                    </div>
                </div>
                
                <div class="card-action article-tags">
                    
                    <a href="/tags/Linux/">
                        <span class="chip bg-color">Linux</span>
                    </a>
                    
                    <a href="/tags/capability/">
                        <span class="chip bg-color">capability</span>
                    </a>
                    
                </div>
                
            </div>
        </div>
        
        
        <div class="article col s12 m6" data-aos="fade-up">
            <div class="article-badge right-badge text-color">
                本篇&nbsp;<i class="far fa-dot-circle"></i>
            </div>
            <div class="card">
                <a href="/2018/05/01/Linux%E6%9D%83%E8%83%BD%E4%B8%8EPAM%E6%9C%BA%E5%88%B6/">
                    <div class="card-image">
                        
                        
                        <img src="/medias/featureimages/8.jpg" class="responsive-img" alt="Linux权能与PAM机制">
                        
                        <span class="card-title">Linux权能与PAM机制</span>
                    </div>
                </a>
                <div class="card-content article-content">
                    <div class="summary block-with-text">
                        
                            
实验环境：uname -a
​      Linux ubuntu 4.4.0-121-generic #145-Ubuntu SMP Fri Apr 13 13:47:23 UTC 2018 x86_64 x86_64 x86_64 G
                        
                    </div>
                    <div class="publish-info">
                            <span class="publish-date">
                                <i class="far fa-clock fa-fw icon-date"></i>2018-05-01
                            </span>
                        <span class="publish-author">
                            
                            <i class="fas fa-bookmark fa-fw icon-category"></i>
                            
                            <a href="/categories/Linux/" class="post-category">
                                    Linux
                                </a>
                            
                            
                        </span>
                    </div>
                </div>

                
                <div class="card-action article-tags">
                    
                    <a href="/tags/Linux-capability/">
                        <span class="chip bg-color">Linux capability</span>
                    </a>
                    
                </div>
                
            </div>
        </div>
        
    </div>
</article>

</div>



<!-- 代码块功能依赖 -->
<script type="text/javascript" src="/libs/codeBlock/codeBlockFuction.js"></script>

<!-- 代码语言 -->

<script type="text/javascript" src="/libs/codeBlock/codeLang.js"></script>


<!-- 代码块复制 -->

<script type="text/javascript" src="/libs/codeBlock/codeCopy.js"></script>


<!-- 代码块收缩 -->

<script type="text/javascript" src="/libs/codeBlock/codeShrink.js"></script>


    </div>
    <div id="toc-aside" class="expanded col l3 hide-on-med-and-down">
        <div class="toc-widget card" style="background-color: white;">
            <div class="toc-title"><i class="far fa-list-alt"></i>&nbsp;&nbsp;目录</div>
            <div id="toc-content"></div>
        </div>
    </div>
</div>

<!-- TOC 悬浮按钮. -->

<div id="floating-toc-btn" class="hide-on-med-and-down">
    <a class="btn-floating btn-large bg-color">
        <i class="fas fa-list-ul"></i>
    </a>
</div>


<script src="/libs/tocbot/tocbot.min.js"></script>
<script>
    $(function () {
        tocbot.init({
            tocSelector: '#toc-content',
            contentSelector: '#articleContent',
            headingsOffset: -($(window).height() * 0.4 - 45),
            collapseDepth: Number('0'),
            headingSelector: 'h2, h3, h4'
        });

        // modify the toc link href to support Chinese.
        let i = 0;
        let tocHeading = 'toc-heading-';
        $('#toc-content a').each(function () {
            $(this).attr('href', '#' + tocHeading + (++i));
        });

        // modify the heading title id to support Chinese.
        i = 0;
        $('#articleContent').children('h2, h3, h4').each(function () {
            $(this).attr('id', tocHeading + (++i));
        });

        // Set scroll toc fixed.
        let tocHeight = parseInt($(window).height() * 0.4 - 64);
        let $tocWidget = $('.toc-widget');
        $(window).scroll(function () {
            let scroll = $(window).scrollTop();
            /* add post toc fixed. */
            if (scroll > tocHeight) {
                $tocWidget.addClass('toc-fixed');
            } else {
                $tocWidget.removeClass('toc-fixed');
            }
        });

        
        /* 修复文章卡片 div 的宽度. */
        let fixPostCardWidth = function (srcId, targetId) {
            let srcDiv = $('#' + srcId);
            if (srcDiv.length === 0) {
                return;
            }

            let w = srcDiv.width();
            if (w >= 450) {
                w = w + 21;
            } else if (w >= 350 && w < 450) {
                w = w + 18;
            } else if (w >= 300 && w < 350) {
                w = w + 16;
            } else {
                w = w + 14;
            }
            $('#' + targetId).width(w);
        };

        // 切换TOC目录展开收缩的相关操作.
        const expandedClass = 'expanded';
        let $tocAside = $('#toc-aside');
        let $mainContent = $('#main-content');
        $('#floating-toc-btn .btn-floating').click(function () {
            if ($tocAside.hasClass(expandedClass)) {
                $tocAside.removeClass(expandedClass).hide();
                $mainContent.removeClass('l9');
            } else {
                $tocAside.addClass(expandedClass).show();
                $mainContent.addClass('l9');
            }
            fixPostCardWidth('artDetail', 'prenext-posts');
        });
        
    });
</script>

    

</main>




    <footer class="page-footer bg-color">
    
        <link rel="stylesheet" href="/libs/aplayer/APlayer.min.css">
<style>
    .aplayer .aplayer-lrc p {
        
        display: none;
        
        font-size: 12px;
        font-weight: 700;
        line-height: 16px !important;
    }

    .aplayer .aplayer-lrc p.aplayer-lrc-current {
        
        display: none;
        
        font-size: 15px;
        color: #42b983;
    }

    
    .aplayer.aplayer-fixed.aplayer-narrow .aplayer-body {
        left: -66px !important;
    }

    .aplayer.aplayer-fixed.aplayer-narrow .aplayer-body:hover {
        left: 0px !important;
    }

    
</style>
<div class="">
    
    <div class="row">
        <meting-js class="col l8 offset-l2 m10 offset-m1 s12"
                   server="netease"
                   type="playlist"
                   id="503838841"
                   fixed='true'
                   autoplay='false'
                   theme='#42b983'
                   loop='all'
                   order='random'
                   preload='auto'
                   volume='0.7'
                   list-folded='true'
        >
        </meting-js>
    </div>
</div>

<script src="/libs/aplayer/APlayer.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/meting@2/dist/Meting.min.js"></script>

    
    <div class="container row center-align" style="margin-bottom: 0px !important;">
        <div class="col s12 m8 l8 copy-right">
            Copyright&nbsp;&copy;
            
                <span id="year">2019-2024</span>
            
            <span id="year">2019</span>
            <a href="/about" target="_blank">Xu Shouyin</a>
            |&nbsp;Powered by&nbsp;<a href="https://hexo.io/" target="_blank">Hexo</a>
            |&nbsp;Theme&nbsp;<a href="https://github.com/blinkfox/hexo-theme-matery" target="_blank">Matery</a>
            <br>
            
            
            
            
            
            
            <span id="busuanzi_container_site_pv">
                |&nbsp;<i class="far fa-eye"></i>&nbsp;总访问量:&nbsp;<span id="busuanzi_value_site_pv"
                    class="white-color"></span>&nbsp;次
            </span>
            
            
            <span id="busuanzi_container_site_uv">
                |&nbsp;<i class="fas fa-users"></i>&nbsp;总访问人数:&nbsp;<span id="busuanzi_value_site_uv"
                    class="white-color"></span>&nbsp;人
            </span>
            
            <br>
            
            <br>
            
        </div>
        <div class="col s12 m4 l4 social-link social-statis">
    <a href="https://github.com/blinkfox" class="tooltipped" target="_blank" data-tooltip="访问我的GitHub" data-position="top" data-delay="50">
        <i class="fab fa-github"></i>
    </a>



    <a href="mailto:1181062873@qq.com" class="tooltipped" target="_blank" data-tooltip="邮件联系我" data-position="top" data-delay="50">
        <i class="fas fa-envelope-open"></i>
    </a>







    <a href="tencent://AddContact/?fromId=50&fromSubId=1&subcmd=all&uin=1181062873" class="tooltipped" target="_blank" data-tooltip="QQ联系我: 1181062873" data-position="top" data-delay="50">
        <i class="fab fa-qq"></i>
    </a>







    <a href="/atom.xml" class="tooltipped" target="_blank" data-tooltip="RSS 订阅" data-position="top" data-delay="50">
        <i class="fas fa-rss"></i>
    </a>

</div>
    </div>
</footer>

<div class="progress-bar"></div>


    <!-- 搜索遮罩框 -->
<div id="searchModal" class="modal">
    <div class="modal-content">
        <div class="search-header">
            <span class="title"><i class="fas fa-search"></i>&nbsp;&nbsp;搜索</span>
            <input type="search" id="searchInput" name="s" placeholder="请输入搜索的关键字"
                   class="search-input">
        </div>
        <div id="searchResult"></div>
    </div>
</div>

<script type="text/javascript">
$(function () {
    var searchFunc = function (path, search_id, content_id) {
        'use strict';
        $.ajax({
            url: path,
            dataType: "xml",
            success: function (xmlResponse) {
                // get the contents from search data
                var datas = $("entry", xmlResponse).map(function () {
                    return {
                        title: $("title", this).text(),
                        content: $("content", this).text(),
                        url: $("url", this).text()
                    };
                }).get();
                var $input = document.getElementById(search_id);
                var $resultContent = document.getElementById(content_id);
                $input.addEventListener('input', function () {
                    var str = '<ul class=\"search-result-list\">';
                    var keywords = this.value.trim().toLowerCase().split(/[\s\-]+/);
                    $resultContent.innerHTML = "";
                    if (this.value.trim().length <= 0) {
                        return;
                    }
                    // perform local searching
                    datas.forEach(function (data) {
                        var isMatch = true;
                        var data_title = data.title.trim().toLowerCase();
                        var data_content = data.content.trim().replace(/<[^>]+>/g, "").toLowerCase();
                        var data_url = data.url;
                        data_url = data_url.indexOf('/') === 0 ? data.url : '/' + data_url;
                        var index_title = -1;
                        var index_content = -1;
                        var first_occur = -1;
                        // only match artiles with not empty titles and contents
                        if (data_title !== '' && data_content !== '') {
                            keywords.forEach(function (keyword, i) {
                                index_title = data_title.indexOf(keyword);
                                index_content = data_content.indexOf(keyword);
                                if (index_title < 0 && index_content < 0) {
                                    isMatch = false;
                                } else {
                                    if (index_content < 0) {
                                        index_content = 0;
                                    }
                                    if (i === 0) {
                                        first_occur = index_content;
                                    }
                                }
                            });
                        }
                        // show search results
                        if (isMatch) {
                            str += "<li><a href='" + data_url + "' class='search-result-title'>" + data_title + "</a>";
                            var content = data.content.trim().replace(/<[^>]+>/g, "");
                            if (first_occur >= 0) {
                                // cut out 100 characters
                                var start = first_occur - 20;
                                var end = first_occur + 80;
                                if (start < 0) {
                                    start = 0;
                                }
                                if (start === 0) {
                                    end = 100;
                                }
                                if (end > content.length) {
                                    end = content.length;
                                }
                                var match_content = content.substr(start, end);
                                // highlight all keywords
                                keywords.forEach(function (keyword) {
                                    var regS = new RegExp(keyword, "gi");
                                    match_content = match_content.replace(regS, "<em class=\"search-keyword\">" + keyword + "</em>");
                                });

                                str += "<p class=\"search-result\">" + match_content + "...</p>"
                            }
                            str += "</li>";
                        }
                    });
                    str += "</ul>";
                    $resultContent.innerHTML = str;
                });
            }
        });
    };

    searchFunc('/search.xml', 'searchInput', 'searchResult');
});
</script>

    <!-- 回到顶部按钮 -->
<div id="backTop" class="top-scroll">
    <a class="btn-floating btn-large waves-effect waves-light" href="#!">
        <i class="fas fa-arrow-up"></i>
    </a>
</div>


    <script src="/libs/materialize/materialize.min.js"></script>
    <script src="/libs/masonry/masonry.pkgd.min.js"></script>
    <script src="/libs/aos/aos.js"></script>
    <script src="/libs/scrollprogress/scrollProgress.min.js"></script>
    <script src="/libs/lightGallery/js/lightgallery-all.min.js"></script>
    <script src="/js/matery.js"></script>

    <!-- Baidu Analytics -->

    <!-- Baidu Push -->

<script>
    (function () {
        var bp = document.createElement('script');
        var curProtocol = window.location.protocol.split(':')[0];
        if (curProtocol === 'https') {
            bp.src = 'https://zz.bdstatic.com/linksubmit/push.js';
        } else {
            bp.src = 'http://push.zhanzhang.baidu.com/push.js';
        }
        var s = document.getElementsByTagName("script")[0];
        s.parentNode.insertBefore(bp, s);
    })();
</script>

    
    <script src="/libs/others/clicklove.js" async="async"></script>
    
    
    <script async src="/libs/others/busuanzi.pure.mini.js"></script>
    

    

    

	
    

    

    

    
    <script src="/libs/instantpage/instantpage.js" type="module"></script>
    

</body>

</html>
